1. Field of the Invention
Exemplary embodiments of the present invention relate to a backlight unit, a method of operating the backlight unit, and a liquid crystal display (“LCD”) device having the backlight unit. More particularly, exemplary embodiments of the present invention relate to a backlight unit for preventing an over-voltage from being applied to a lamp, a method of operating the backlight unit, and an LCD device having the backlight unit.
2. Description of the Related Art
A backlight unit includes a light source. The backlight unit typically transforms light generated from the light source into a planar light having uniform brightness, and provides a liquid crystal display (“LCD”) panel with the planar light.
Examples of the light source include a cold cathode fluorescent lamp (“CCFL”), an external electrode fluorescent lamp (“EEFL”), and a light-emitting diode (“LED”), and various other similar devices.
In order to generate the light in the backlight unit, an operating voltage is provided to the lamp. An element for providing the operating voltage is an operation driver (also referred to as an inverter). The operation driver applies a high voltage to the lamp so that the lamp generates light.
That is, the backlight unit includes a lamp generating light and an operation driver that converts a direct current (“DC”) voltage of an input voltage to an alternating current (“AC”) voltage and boosts the voltage to provide the lamp with the boosted voltage. The operation driver provides a high voltage for turning on the lamp in an initial stage, and controls a current flowing through the lamp to maintain uniform brightness of the lamp.
However, when a portion of the lamps and its associated driving circuitry breaks down and thus a portion of the lamp and/or its associated driving circuitry is open, e.g., current is unable to flow therethrough, it is difficult to detect the open lamp. Therefore, the current flowing through the other lamps is increased to maintain uniform brightness of the lamps in an abnormal state.